Are Probiotics Bad For You?

Written by Dr. Steve Chaney on . Posted in Probiotics

Are Probiotics Worthless?

Author: Dr. Stephen Chaney

 

are probiotics bad for youProbiotics (friendly gut bacteria) are all the rage. There is big money to be made, so the internet is ablaze with all the amazing things probiotics can do for you. Of course, most of those articles are posted by companies wanting to sell you their miracle mixture of probiotic bacteria.

In the last few weeks, you may have seen headlines proclaiming that probiotics are worthless. You just poop them out. Even worse, they may be upsetting the natural balance of bacteria in your gut. Are probiotics bad for you?  They may be.

As usual, the truth is somewhere in the middle. Before I start sorting out fact from fiction, let me remind you of some important facts about gut bacteria that I covered in a recent article of “Health Tips From The Professor”:

  • The composition of bacteria in our gut is influenced by what we eat. For example, meat eaters have a completely different composition of gut bacteria than vegetarians.
  • Fiber from whole plant foods is a major food source for healthy gut bacteria.
  • Each plant-based food group and each food within that group has a unique blend of fibers. We should probably aim for a wide variety of whole plant foods in our diet.

Are Probiotics Worthless?

 

are probiotics bad for you studyLet’s start with the study (N. Zmora et al, Cell 174, 1388-1405, 2018 ) that generated the headlines proclaiming that probiotics were worthless.

The characteristics of the study with my comments are as follows:

  • The study had 15 subjects who were given either a commercially available probiotic supplement or a placebo containing cellulose. It was a very small study.
  • The probiotic supplement contained 25 billion colony forming units of 11 commonly used strains of bacteria. Its manufacturer claimed the bacteria survived stomach acid and colonized the intestine, but no references were given for published clinical studies backing up that claim. It is buyer beware in the supplement industry. I would not believe any claims about a probiotic supplement that were not backed up by published clinical studies.
  • The investigators measured bacterial colonization of the mucosal cells lining the intestine rather than the population of bacteria that ended up in the feces. This is the “gold standard” for measuring colonization of the intestine by probiotic bacteria. However, it requires a colonoscopy before the study started and a second colonoscopy 3 weeks later. As any of you who have had a colonoscopy can attest, this is a very invasive procedure. It probably accounts for the small size of the study. In fact, the study started with 28 subjects and 13 dropped out, one after suffering a serious adverse reaction to the first colonoscopy. My point is simply that I don’t expect to see a lot of this type of study.

are probiotics bad for you supplementsThe results of the study with my comments are as follows:

  • Overall, the particular probiotic supplement used in this study didn’t work very well. There was minimal colonization of the intestinal mucosal cells by the bacteria in the probiotic supplement. Some did better than others, but the net colonization was small. We don’t know whether the results would have been the same with other probiotic supplements, but this is the finding that generated all the headlines. However, it is the rest of the study that is interesting.
  • The probiotic supplement worked better for some subjects than for others. Some of the subjects in the study were “permissive.” The probiotic cells colonized their intestinal mucosal cells with high efficiency. Other subjects were “resistant.”  Probiotic bacteria had a great deal of difficulty colonizing their intestinal mucosal cells. This doesn’t surprise me. Most clinical studies report an average result. They don’t report individual variations. This is one of the first studies to report on individual variation of probiotic colonization. As such, it has important implications. It means that even though you may be taking a probiotic supplement that has been “clinically proven” to survive stomach acid and colonize the intestine, it may not work well for you. But, wait, the study gets even more interesting.
  • How well the probiotic supplement worked depended on the population of bacteria in the intestine to begin with. “Permissive” and “resistant” subjects had very different species of bacteria in their intestine at the beginning of the trial. There was a characteristic grouping of bacteria in “permissive” subjects and a different characteristic grouping of bacteria in “resistant” subjects. This is the part of the study that should have generated headlines. Let’s put this part of the study into perspective.

We each have around 38 trillion bacteria in our intestines. Let’s assume that all 25 billion bacteria in the probiotic supplement make it into the intestine intact. You have just dropped them into hostile territory where they are outnumbered 1,000 to 1. We know that some bacteria secret substances that support the growth of “like-minded” bacteria. That’s why certain species of bacteria tend to cluster together. We also know that bacteria secret toxins, so they can out-compete bacteria they don’t like. So, it is no wonder the survival of the probiotic bacteria depends on which species of bacteria are already populating the intestine when they arrive on the scene.

This study leaves a lot of unanswered questions:

  • What determined the original population of gut bacteria? Was it the genetics or health of the subject? Or, was it the food they were eating? We simply don’t know.
  • We were sending these probiotic bacteria into hostile territory. Were we giving them the food they needed to survive? Would the results have been different for the “resistant” subjects if they had been eating a different kind of fiber-rich foods, or taken a prebiotic supplement? Again, we just don’t know.

If we want to optimize the results of probiotic supplementation, these are the questions we should be asking.

 

Are Probiotics Bad For You?

are probiotics bad for you thumbs downNow, let’s turn to the study (J. Suez et al, Cell 174, 1406-1423, 2018) generating the headlines saying that probiotic supplements may be bad for you. This study was looking specifically at the use of probiotics following antibiotic use.

The study reported when probiotics are used following antibiotic use, they delay, rather than enhance, the recovery of intestinal bacteria back to the same number and type of bacteria that existed prior antibiotic use. That’s the finding that generated all the headlines. Let’s put that into perspective.

Both the headlines and interpretation of the data were inaccurate.

  • Probiotics actually had a relatively small effect on the ability to regain your “normal” population of intestinal bacteria. The headlines made it sound as if the delay was significant and that you never regained your “normal” population of intestinal bacteria. In fact by one measure, the population of intestinal bacteria was 70% normal by 5 days, 80% normal by 20 days, and 95% normal by 90 days.
  • Poop pills work better but will probably never be popular. When the investigators extracted intestinal bacteria from the subject’s poop and put them into pills prior to the study, the poop pills restored the “normal” population of intestinal bacteria much more quickly. However, I doubt that poop pills will become popular any time soon.
  • Your “normal” population of intestinal bacteria may not be the optimal population of intestinal bacteria. The headlines implied that the fact you never recovered your “normal” population of intestinal bacteria was a bad thing. That assertion assumes that all of us have the optimal population of intestinal bacteria to begin with, an assertion that almost any expert in the field would find absurd. The last time I checked, one of the major reasons for taking probiotic supplements was to change our population of intestinal bacteria for the better.

The study ignores the major reasons for taking a probiotic supplement after antibiotic use. Most people are not taking the probiotic supplement to restore their original population of intestinal bacteria. They are taking it to:

  • Prevent “bad guys” like yeast from filling the void caused by the antibiotics.
  • Improve digestion. Some strains of intestinal bacteria play an important role in digestion. Because antibiotics wipe out those bacteria, they often cause gas, diarrhea, and bloating. After antibiotic use, people are taking probiotic bacteria with digestive benefits to eliminate those digestive issues as quickly as possible.
  • Strengthen the immune system. People are generally taking antibiotics to fight some sort of infection. Some strains of intestinal bacteria play an important role in immunity. Because antibiotics wipe out those bacteria, they weaken the immune system. After antibiotic use, people are taking probiotics to strengthen the immune system as quickly as possible

In short, taking probiotic supplements that are proven to improve digestion and strengthen the immune system play an important role in minimizing the side effects of antibiotic use.

What Does This Mean For You?

are probiotics bad for you truthAt the beginning of this article I said; “The truth lies somewhere in between.” The first study is a perfect example.

  • It was valuable in that it challenged the assertion by some manufacturers that their probiotics survive stomach acid and work equally well for everyone. At the very least, it suggests that we should demand clinical proof that any probiotic supplement colonizes the intestine and provides a health benefit before we use it.
  • The most interesting finding from the first study is that probiotics work much better for some people than for others, and how well they work depends on the population of bacteria in our gut prior to taking the antibiotic. We have much more to learn about this individual variability, and how to control it.

Until we know more, my best advice is to eat a fiber-rich, primarily plant-based diet with as many different varieties of fruits, vegetables, whole grains, and legumes as possible. Providing a variety of fibers is important because at least some of them will likely support the growth of the bacteria in the probiotic supplement. Prebiotics may be of some help, but only if they have been shown to be effective for the particular strains of probiotic bacteria they are paired with.

The second study was much less enlightening. It reported that taking a probiotic after antibiotic use slowed the return to the original population of intestinal bacteria. My response to that is: “So what?”

  • The effect was minimal.
  • The purpose of probiotics is to improve on the population of intestinal bacteria, not to return to the same population of bacteria you had prior to antibiotic use.
  • Probiotics are taken after antibiotic use for reasons that have nothing to do with restoring the original population of intestinal bacteria.

 

The Bottom Line

 

Two recent studies have challenged the benefits of probiotic use.

The first study provided some valuable insights.

  • It reported that a particular probiotic supplement did a very poor job of colonizing the intestine. We have no idea whether that would apply to other probiotic supplements, but that was the result that generated all the headlines. At the very least, it suggests that we should demand clinical proof that any probiotic supplement colonizes the intestine and provides a health benefit before we use it.
  • However, the most interesting finding from the first study is that probiotics work much better for some people than for others, and how well they work depends on the population of bacteria in our gut prior to taking the antibiotic. We have much more to learn about this individual variability, and how to control it.

The second study was much less enlightening. It reported that taking a probiotic after antibiotic use slowed the return to the “normal” population of intestinal bacteria that were present before antibiotic use. My response to that is: “So what?”

  • The purpose of probiotics is to improve on the population of intestinal bacteria, not to return to the same population of intestinal bacteria you had prior to taking an antibiotic.
  • Probiotics are taken after antibiotic use for reasons that have nothing to do with restoring the original population of intestinal bacteria.

For more details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Does Magnesium Optimize Vitamin D Levels?

Posted February 12, 2019 by Dr. Steve Chaney

The Case For Holistic Supplementation

Author: Dr. Stephen Chaney

 

Does magnesium optimize vitamin D levels?

magnesium optimize vitamin dOne of the great mysteries about vitamin D is the lack of correlation between vitamin D intake and blood levels of its active metabolite, 25-hydroxyvitamin D. Many people who consume RDA levels of vitamin D from foods and/or supplements end up with low blood levels of 25-hydroxyvitamin D. The reason(s) for this discrepancy between intake of vitamin D and blood levels of its active metabolite are not currently understood.

Another great mystery is why it has been so difficult to demonstrate benefits of vitamin D supplementation. Association studies show a strong correlation between optimal 25-hydroxyvitamin D levels and reduced risk of heart disease, cancer, and other diseases. However, placebo-controlled clinical trials of vitamin D supplementation have often come up empty. Until recently, many of those studies did not measure 25-hydroxyvitamin D levels. Could it be that optimal levels of 25-hydroxyvitamin D were not achieved?

The authors of the current study hypothesized that optimal magnesium status might be required for vitamin D conversion to its active form. You are probably wondering why magnesium would influence vitamin D metabolism. I had the same question.

The authors pointed out that:

  • Magnesium status affects the activities of enzymes involved in both the synthesis and degradation of 25-hydroxyvitamin D.
  • Some clinical studies have suggested that magnesium intake interacts with vitamin D intake in affecting health outcomes.
  • If the author’s hypothesis is correct, it is a concern because magnesium deficiency is prevalent in this country. In their “Fact Sheet For Health Professionals,” the NIH states that “…a majority of Americans of all ages ingest less magnesium from food than their respective EARs [Estimated Average Requirement]; adult men aged 71 years and older and adolescent females are most likely to have low intakes.” Other sources have indicated that magnesium deficiency may approach 70-80% for adults over 70.

If the author’s hypothesis that magnesium is required for vitamin D activation is correct and most Americans are deficient in magnesium, this raises some troubling questions.

  • Most vitamin D supplements do not contain magnesium. If people aren’t getting supplemental magnesium from another source, they may not be optimally utilizing the vitamin D in the supplements.
  • Most clinical studies involving vitamin D do not also include magnesium. If most of the study participants are deficient in magnesium, it might explain why it has been so difficult to show benefits from vitamin D supplementation.

Thus the authors devised a study (Q Dai et al, American Journal of Clinical Nutrition, 108: 1249-1258, 2018 ) to directly test their hypothesis.

 

How Was The Study Designed?

magnesium optimize vitamin d studyThe authors recruited 180 volunteers, aged 40-85, from an ongoing study on the prevention of colon cancer being conducted at Vanderbilt University. The duration of the study was 12 weeks. Blood was drawn at the beginning of the study to measure baseline 25-hydroxyvitamin D levels. Three additional blood draws to determine 25-hydroxyvitamin D levels were performed at weeks 1, 6, and 12.

Because high blood calcium levels increase excretion of magnesium, the authors individualized magnesium intake based on “optimizing” the calcium to magnesium ratio in the diet rather than giving everyone the same amount of magnesium. The dietary calcium to magnesium ratio for most Americans is 2.6 to 1 or higher. Based on their previous work, they considered an “ideal” calcium to magnesium ratio to be 2.3 to 1. The mean daily dose of magnesium supplementation in this study was 205 mg, with a range from 77 to 390 mg to achieve the “ideal” calcium to magnesium ratio. The placebo was an identical gel capsule containing microcrystalline cellulose.

Two 24-hour dietary recalls were conducted at baseline to determine baseline dietary intake of calcium and magnesium. Four additional 24-hour dietary recalls were performed during the 12-week study to assure that calcium intake was unchanged and the calcium to magnesium ratio of 2.3 to 1 was achieved.

In short this was a small study, but it was very well designed to test the author’s hypothesis.

 

Does Magnesium Optimize Vitamin D Levels?

 

does magnesium optimize vitamin d levelsThis was a very complex study, so I am simplifying it for this discussion. For full details, I refer you to the journal article (Q Dai et al, American Journal of Clinical Nutrition, 108: 1249-1258, 2018).

The most significant finding was that magnesium supplementation did affect blood levels of 25-hydroxyvitamin D. However, the effect of magnesium supplementation varied depending on the baseline 25-hydroxyvitamin D level at the beginning of the study.

  • When the baseline 25-hydroxyvitamin D was 20 ng/ml or less (which the NIH considers inadequate), magnesium supplementation had no effect on 25-hydroxyvitamin D levels.
  • When the baseline 25-hydroxyvitamin D was 20-30 ng/ml (which the NIH considers the lower end of the adequate range), magnesium supplementation increased 25-hydroxyvitamin D levels.
  • When the baseline 25-hydroxyvitamin D level approached 50 ng/ml (which the NIH says may be “associated with adverse effects”), magnesium supplementation lowered 25-hydroxyvitamin D levels.

The simplest interpretation of these results is:

  • When vitamin D intake is inadequate, magnesium cannot magically create 25-hydroxyvitamin D from thin air.
  • When vitamin D intake is adequate, magnesium can enhance the conversion of vitamin D to 25-hydroxyvitamin D.
  • When vitamin D intake is too high, magnesium can help protect you by lowering 25-hydroxyvitamin D levels.

The authors concluded: “Our findings suggest that optimal magnesium status may be important for optimizing 25-hydroxyvitamin D status. Further dosing studies are warranted…”

 

What Does This Study Mean For You?

magnesium optimize vitamin d for youThis was a groundbreaking study that has provided novel and interesting results.

  • It provides the first evidence that optimal magnesium status may be required for optimizing the conversion of vitamin D to 25-hydroxyvitamin D.
  • It suggests that optimal magnesium status can help normalize 25-hydroxyvitamin D levels by increasing low levels and decreasing high levels.

However, this was a small study and, like any groundbreaking study, has significant limitations. For a complete discussion of the limitations and strengths of this study I refer you to the editorial (S Lin and Q Liu, American Journal of Clinical Nutrition, 108: 1159-1161, 2018) that accompanied the study.

In summary, this study needs to be replicated by larger clinical studies with a more diverse study population. In order to provide meaningful results, those studies would need to carefully control and monitor calcium, magnesium, and vitamin D intake. There is also a need for mechanistic studies to better understand how magnesium can both increase low 25-hydroxyvitamin D levels and decrease high 25-hydroxyvitamin D levels.

However, assuming the conclusions of this study to be true, it has some interesting implications:

  • If you are taking a vitamin D supplement, you should probably make sure that you are also getting the DV (400 mg) of magnesium from diet plus supplementation.
  • If you are taking a calcium supplement, you should check that it also provides a significant amount of magnesium. If not, change supplements or make sure that you get the DV for magnesium elsewhere.
  • I am suggesting that you shoot for the DV (400 mg) of magnesium rather than reading every label and calculating the calcium to magnesium ratio. The “ideal” ratio of 2.3 to 1 is hypothetical at this point. A supplement providing the DV of both calcium and magnesium would have a calcium to magnesium ratio of 2.5, and I would not fault any manufacturer for providing you with the DV of both nutrients.
  • If you are taking high amounts of calcium, I would recommend a supplement that has a calcium to magnesium ratio of 2.5 or less.
  • If you are considering a magnesium supplement to optimize your magnesium status, you should be aware that magnesium can cause gas, bloating, and diarrhea. I would recommend a sustained release magnesium supplement.
  • Finally, whole grains and legumes are among your best dietary sources of magnesium. Forget those diets that tell you to eliminate whole food groups. They are likely to leave you magnesium-deficient.

Even if the conclusions of this study are not confirmed by subsequent studies, we need to remember that magnesium is an essential nutrient with many health benefits and that most Americans do not get enough magnesium in their diet. The recommendations I have made for optimizing magnesium status are common-sense recommendations that apply to all of us.

 

The Case For Holistic Supplementation

 

magnesium optimize vitamin d case for holistic supplementationThis study is one of many examples showing that a holistic approach to supplementation is superior to a “magic bullet” approach where you take individual nutrients to solve individual problems. For example, in the case of magnesium and vitamin D:

  • If you asked most nutrition experts and supplement manufacturers whether it is important to provide magnesium along with vitamin D, their answer would likely be “No”. Even if they are focused on bone health, they would be more likely to recommend calcium along with vitamin D than magnesium along with vitamin D.
  • If your doctor has tested your 25-hydroxyvitamin D levels and recommended a vitamin D supplement, chances are they didn’t also recommend that you optimize your magnesium status.
  • Clinical studies investigating the benefits of vitamin D supplementation never ask whether magnesium intake is optimal.

That’s because most doctors and nutrition experts still think of nutrients as “magic bullets.” I cover holistic supplementation in detail in my book “Slaying The Supplement Myths.”  Other examples that make a case for holistic supplementation that I cover in my book include:

  • A study showing that omega-3 fatty acids and B vitamins may work together to prevent cognitive decline. Unfortunately, most studies looking at the effect of B vitamins on cognitive decline have not considered omega-3 status and vice versa. No wonder those studies have produced inconsistent results.
  • Studies looking at the effect of calcium supplementation on loss of bone density in the elderly have often failed to include vitamin D, magnesium, and other nutrients that are needed for building healthy bone. They have also failed to include exercise, which is essential for building healthy bone. No wonder some of those studies have failed to find an effect of calcium supplementation on bone density.
  • A study reported that selenium and vitamin E by themselves might increase prostate cancer risk. Those were the headlines you might have seen. The same study showed Vitamin E and selenium together did not increase prostate cancer risk. Somehow that part of the study was never mentioned.
  • A study reported that high levels of individual B vitamins increased mortality slightly. Those were the headlines you might have seen. The same study showed that when the same B vitamins were combined in a B complex supplement, mortality decreased. Somehow that observation never made the headlines.
  • A 20-year study reported that a holistic approach to supplementation produced significantly better health outcomes.

In summary, vitamins and minerals interact with each other to produce health benefits in our bodies. Some of those interactions we know about. Others we are still learning about. When we take high doses of individual vitamins and minerals, we create potential problems.

  • We may not get the full benefit of the vitamin or mineral we are taking because some other important nutrient(s) may be missing from our diet.
  • Even worse, high doses of one vitamin or mineral may interfere with the absorption or enhance the excretion of another vitamin or mineral. That can create deficiencies.

The same principles apply to our diet. I mentioned earlier that whole grains and legumes are among the best dietary sources of magnesium. Eliminating those two foods from the diet increases our risk of becoming magnesium deficient. And, that’s just the tip of the iceberg. Any time you eliminate foods or food groups from the diet, you run the risk of creating deficiencies of nutrients, phytonutrients, specific types of fiber, and the healthy gut bacteria that use that fiber as their preferred food source.

The Bottom Line

 

A recent study suggests that optimal magnesium status may be important for optimizing 25-hydroxyvitamin D status. This is one of many examples showing that a holistic approach to supplementation is superior to a “magic bullet” approach where you take individual nutrients to solve individual problems. For example, in the case of magnesium and vitamin D:

  • If you asked most nutrition experts and supplement manufacturers whether it is important to provide magnesium along with vitamin D, their answer would likely be “No.”  Even if they are focused on bone health, they would be more likely to recommend calcium along with vitamin D than magnesium along with vitamin D.
  • If your doctor has tested your 25-hydroxyvitamin D levels and recommended a vitamin D supplement, chances are he or she did not also recommend that you optimize your magnesium status.
  • Clinical studies investigating the benefits of vitamin D supplementation never ask whether magnesium intake is optimal. That may be why so many of those studies have failed to find any benefit of vitamin D supplementation.

I cover holistic supplementation in detail in my book “Slaying The Supplement Myths” and provide several other examples where a holistic approach to supplementation is superior to taking individual supplements.

In summary, vitamins and minerals interact with each other to produce health benefits in our bodies. Some of those interactions we know about. Others we are still learning about. Whenever we take high doses of individual vitamins and minerals, we create potential problems.

  • We may not get the full benefit of the vitamin or mineral we are taking because some other important nutrient(s) may be missing from our diet.
  • Even worse, high doses of one vitamin or mineral may interfere with the absorption or enhance the excretion of another vitamin or mineral. That can create deficiencies.

The same principles apply to what we eat. For example, whole grains and legumes are among the best dietary sources of magnesium. Eliminating those two foods from the diet increases our risk of becoming magnesium deficient. And, that’s just the tip of the iceberg. Any time you eliminate foods or food groups from the diet, you run the risk of creating deficiencies.

For more details about the current study and what it means to you read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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